When does the breakdown process start with trash in landfills?

Answers

Immediately. The items in a landfill will break down at different rates depending on what they are and how quickly their materials decompose, but organic matter such as food waste, leaves, or human or animal waste will begin breaking down chemically even before it reaches the landfill. The degradation of organic matter is the chief driver of composting, where the matter breaks down to simpler compounds, usually generating odors, gases such as methane and often attracts bacteria or larger scavengers like birds or rodents. Inorganic materials such as plastics and metals will naturally take a much longer time to break down, hence the meant-to-be-shocking statistics you hear about how many hundreds of years it will take for a single disposable diaper or milk bottle to decompose in a landfill. Creating and managing landfills is a complicated process of science, engineering and land use, and managing the decomposition of materials in it is a big job. Dumps may seem quite simple but in order to be safe and effective they have to be placed, filled and managed very carefully to avoid impacts to nearby communities or ecosystems.